Regulation by opinion
It seem to me, more and more, that the Authority appears to regulate on the basis of opinion, rather than on the basis of law. At least, in the USA, anyone can request a (legally binding) ruling stating the FAA's official position on any subject from the FAA equivalent of the OLC.
As GlenB has shown, getting anything in writing from CASA doesn't really mean a thing as 1) there appears to be no accountability, 2) the regulations only mean what one person thinks the regulations should mean and 3) what one CASA person thinks the regulations should mean will differ from what another CASA person thinks it should mean.
Perhaps the Regulations should be more accurately renamed Suggestions.